Tetra Engineering has announced its schedule for HRSG & Combined Cycle training events in 2016. This year we will be hosting training courses in Utah and Connecticut, USA, as well as in France and a new event in Dubai, UAE. See our training page for more details.
Responding to changes in the market, many combined cycle plants are seizing new opportunities by adapting their operation to run more flexibly and at lower loads than the original design intended. In a recent article in Power Magazine Tetra Engineers David Moelling, Peter Jackson and James Malloy outline some of the challenges that plants must face to ensure the long-term integrity of the steam cycle.
Tetra Engineering supports plants across five continents in overcoming the engineering difficulties associated with flexible / low-load operation of HRSGs, Power Piping to the Steam Turbine or host processes, as well as the condenser. Our services include assessing the performance and degradation impact of flexible service which feeds into setting appropriate inspection intervals for different components and developing the associated inspection plans.
See this short flyer for more information, or get in touch with your nearest office for details about how we can help you.
Tetra Engineering provides services to assist Cement Plant Owners and Operators in implementing, maintaining and improving all types of Heat Recovery Systems. Our Heat Recovery Steam Generator and steam cycle services have been applied to Rotary Kiln Waste Heat recovery power generation systems. Whether addressing problems with fouling, or assessing plant modifications for performance improvements, contact Tetra to reduce your energy costs and increase reliability.
Tetra Engineering will be presenting our technical paper on "Impact of Startup Purge Credit on Combined Cycle Plant Operation" at the ASME Power and Energy Conversion 2015 Conference in San Diego, California, USA on June 30, 2015. It describes the technical basis for purge credit operation and provides an example of the impact on fatigue lifetime in key Heat Recovery Steam Generator components.
See the full program at the ASME website here.
ASME B31.1 places practice requirements on Operators for the maintenance of their Covered Piping Systems (CPSs). Condition Assessments are required on a regular basis, associated with good record-keeping for traceability. Over time this generates large volumes of documentation and inspection history data, therefore a coherent solution to knowledge management is needed.
PipeVue 2.0 was developed by Tetra Engineering to store and organize large amounts of inspection data in one network-based solution, easy accessible for both plant operators as well as engineers planning yearly inspections. PipeVue 2.0 has three modules covering:
- Pipe Hangers & Supports;
- Flow-accelerated Corrosion inspection data; and
- Grade 91 Weld inspection data
The software stores hanger/support setting information (hot/cold), inspection notes, photos, NDT data and associated design documentation (PDF drawings & manuals) in a simple and categorized manner, with 3D-visualization of all components.
The user can add new data and save to a networked database, where it will be instantly accessible for other users. The software is available as a deliverable from Piping Inspections, or independently as a Knowledge Management System for Power Piping. Engineering support from Tetra is available as an option, creating an instant channel between plant personnel and third party engineers.
At Combined Cycle Power Plants the Heat Recovery Steam Generator (HRSG) is an easily-overlooked, but key component, providing steam to the steam turbine and to attached process steam hosts. While base-loaded HRSGs tend to be the most reliable - cycled or two-shifted plants suffering from accelerated damage - the importance of allocating sufficient resources to maintenance of the HRSG is often only realised in hindsight.
Even a simple visual HRSG Inspection during an outage can provide useful information about the how the HRSG is aging and what maintenance should be planned to ensure ongoing reliability. Many have experienced the sudden drop in reliability that comes when a neglected HRSG begans having tube failures in one area, causing frequent shutdowns that later aggravate other incipient problems that could have been avoided by simple performing a Visual Inspection, and taking remedial action early on.
Tetra Engineering has been performing HRSG Inspections for over fifteen years - over 500 Inspections to date! - and provides an integrated service that supports Owners and Operators throughout the full HRSG life-cycle. In addition to the HRSG Inspections we also perform HRSG Condition Assessments, in which we review not only the present condition of the HRSG Unit but also how historical operation has affected its integrity.
As part of its HRSG Life Management services, Tetra also draws on its unique skill set, including extensive field experience and engineering analysis, to assess the HRSG's susceptibility to certain damage mechanisms (e.g. Fatigue, Creep, FAC, Corrosion) and produced customised HRSG Inspection Plans. Those plans can be used by inspectors and NDT-teams during plant outages to target HRSG Inspections where damage is most likely to be found.
For more information on HRSG Inspections and Inspection Planning, see our Field Services page.
Tetra Engineering will have a booth next month at the upcoming PowerGen Middle East in Abu Dhabi on October 12-14. We will present our latest service offerings including Field Services, Engineering Analysis, 3rd Party Engineering, and Training. Come see us at the N21 booth, and enter your business card for your chance to win a Wilesco Steam Engine Generator!
Announcing Tetra Engineering's Fall 2014 USA Training Seminar: Effective Operation of HRSGs on November 12 & 13 at The Simsbury Inn, Simsbury, Connecticut USA. See this link for more information on the syllabus.
The sudden contact of low-temperature water droplets on high temperature steel leads to what are commonly called thermal impingement stresses. These tensile stresses can be very, very high and lead to yielding of the steel; resulting in visible, local bulging of the pipe and/or cracking of the internal wall. Frequent incidences of this problem with associated failures are observed in thermal power plants; they often occur in Main Steam Bypass and Hot Reheat Bypass Power Piping or in attemporator sprays.
Good control logic and operator awareness is crucial to ensure that spray water doesn't build up when valves are closed, that sprays are not exceeding their proper flow range or that there is over-spraying into the steam.
Inspection techniques vary depending on access but may include Ultrasonic Testing (UT) and Remote Visual Inspection (RVI) by videoscope, as well as hardness testing of sensitive materials. Tetra prepares an Inspection Plan for O&M staff to follow to ensure that the condition of the relevant components is sufficiently monitored to mitigate risks.